Three-dimensional (3D) data collection of an object may rely on speed, accuracy, and portability for purposes such as reproduction. 3D data collection technique may be applied in fields of digital imaging, computer animation, topography, reconstructive and plastic surgery, dentistry, internal medicine, rapid prototyping, etc.
Optical apparatuses are developed to collect the shape, contour, position or other information of the object in digitized form. For example, an optical apparatus using triangulation may include two image sensors to receive light reflected from an object and then determines three-dimensional spatial locations for points where the light reflects from the object. Another type of optical apparatus, which includes merely one single image sensor, may also be provided to collect 3D information. Such optical apparatus is relatively compact as compared to the apparatus having two image sensors.
An example of a three-mirror panoramic camera is disclosed in U.S. Pat. No. 8,451,318 B2, which requires a sophisticated optical system (including three-mirror subsystem) to collect enough image data. Such three-mirror subsystem requires a relatively greater space to have a relatively greater depth of focus and may adversely affect miniaturization.
The IEEE paper (http://eia.udg.es/˜qsalvi/papers/2005-ICRA.pdf) entitled “Omnidirectional Depth Computation from a Single Image” may disclose another example of a three-mirror panoramic camera, which requires highly precise alignment (calibration) of laser, a parabolic mirror, a conical mirror and a camera. Moreover, the collected image data are computed by a laser triangulation technique to determine an omnidirectional depth.